Angiotensin II (AII) evokes a biphasic increase in inositol 1,4,5-trisphosphate (Ins(1,4,5)P3) levels in adrenal glomerulosa cells, with an extracellular Ca(2+)-independent early peak followed by a secondary sustained elevation that is highly dependent on the presence of extracellular Ca2+. The Ca(2+)-dependent sustained phase of agonist-induced Ins(1,4,5)P3 production was closely correlated wi...

Cortical vesicles (CV) possess components critical to the mechanism of exocytosis. The homotypic fusion of CV centrifuged or settled into contact has a sigmoidal Ca2+ activity curve comparable to exocytosis (CV-PM fusion). Here we show that Sr2+ and Ba2+ also trigger CV-CV fusion, and agents affecting different steps of exocytotic fusion block Ca2+, Sr2+, and Ba2+-triggered CV-CV fusion. The ma...

2014 It is pointed out that the transverse couplings and, accessorily, the longitudinal scattering by doping and phonons broaden enough the 2d van Hove singularities of Cu O2 planes to prevent their spontaneous Jahn Teller splitting. The tetragonal-orthorhombic phase changes observed in La2-x Srx Cu O4-y and Y Ba2 Cu3 O7-03B4 have then different origins and nature. In good crystals, this broade...

We have performed first-principles density functional theory calculations, incorporated with van der Waals interactions, to study CO2 adsorption and diffusion in nanoporous solid – OMS2 (Octahedral Molecular Sieve). We found the charge, type, and mobility of a cation, accommodated in a porous OMS-2 material for structural stability, can affect not only the OMS-2 structural features but also CO2...

Barium isotopes could be a novel tracer in low-temperature geochemical processes such as the Ba cycle rivers and oceans. Equilibrium isotope fractionation between Ba-hosting minerals aqueous solution is of great importance for applications geochemistry, but it remains poorly constrained. In this study, we performed first-principles calculations based on density functional theory (DFT) to determ...

The movement and interaction of multiple ions passing through in single file underlie various fundamental K(+) channel properties, from the effective conduction of K(+) ions to channel blockade by Ba(2+) ions. In this study, we used single-channel electrophysiology and x-ray crystallography to probe the interactions of Ba(2+) with permeant ions within the ion conduction pathway of the MthK K(+)...

Sphingolipids stimulate the release of Ca2+ from intracellular stores. However, the mechanism by which this process occurs has not been characterized. Through single-channel recording from microsomes incorporated into planar lipid bilayers, we describe a novel channel that gates Ba2+ in response to sphingosylphosphorylcholine. The channel is both ligand-gated and voltage-modulated. Maximal open...